1. Field of the Invention
The present invention relates to a method of producing paper webs coated on both sides and to an apparatus for the application of such method.
2. Description of the Related Art
More exactly, the present invention concerns a so-called multiple coating method in which a liquid medium is applied twice, successively on each paper side. Such multiple coating method is known from the magazine "Wochenblatt fur Papierfabrikation" No. 11/12, 1974, pages 339 through 400; refer specifically to FIG. 4 on page 396. Illustrated there are four coaters of essentially the same structure. In each of the coaters, the paper web runs over a backing roll, with liquid medium being applied directly onto the paper web. Known from FIG. 1 of the same publication, however, is also the following: A precoat can first be applied indirectly onto each paper side, followed by a top coating applied by a direct method. Refer to "Wochenblatt fur Papierfabrikation" No. 10, 1955, pages 436 through 443, notably FIG. 15.